Knocking sound from engine on cold start - HELP
 

Guys,

I have a MY03 WRX with PPP that I bought in Oct. It has just turned 20k miles. Was serviced at 18k then garaged for almost 8 months.

When I bought it I had a little problem with the engine light coming on. To cut a long story short, the dealer replaced 2 'tumble motors'. They also said the oil appeared 'creamy'. Although I did not believe them, having already looked at the oil myself, I agreed to have an oil change.

They put Castrol GTX Magnatec 10w40 in:nono: Not too pleased, but at least it was changed.

All has been well for the last 3-4 weeks until Friday when the engine light came on again:cry: I called Subaru Assistance who told me not to worry too much as long as there were no other symptoms and the light went off, which it did after a while.

Now, today I started the car and there was a knocking sound coming from the engine. Nothing too loud, sounded a bit like someone knocking a table with a gloved hand (if you see what I mean) In that it was not too harsh a knock, sounded more 'solid', rather than tinny.

It was certainly not what I would call loud, but you could hear it with the bonnet closed.

Anyway, I drove the car to my mums and checked again. The noise is gone:Suspiciou

Anyone know what might be causing this? Should I be worried about it?

Any help would be very much appreciated. This is my first Scoob and I worry constantly about damaging the engine. I always warm/cool the engine properly.

Thanks in advance

Just been out and started the car again. I could hear the noise again if I put my ear close to the front grill.

Anyone have any idea what this could be??

sounds like piston slap. usually disappears when the engine has warmed up. Apparently it is quite common

Is that something I should be worried about? Will it cause damage?

Thanks for the reply, but I need more info please, I am a complete newb with Scoobies, and I know very little about engines anyway!!:Whatever_

"Creamy" oil would indicate water contamination. With modern oils and engine breather systems this is quite rare unless there is a head gasket problem, although sitting for 8 months certainly doesn't help!
Another possibility regarding the noise is the cam belt tensioner which can knock against it's stop until the engine has warmed slightly and the belt rotation smooths.
JohnD

Thanks for the advice. The oil definately was not creamy. I checked it the day before it went to the dealer so I know he was lying.

I have also ever since kept a very close eye on it (checked every day) and it most certainly is not creamy.

The noise does appear to be coming from the direction of the belts at the front of the engine, would this be the cam belt?? And, yes it does disappear once the engine is warm.